1. Field of the Invention
This invention relates generally to exercise apparatus, and more particularly to exercise apparatus for enforcing the proper use of such apparatus and to provide motivation for using the apparatus.
2. Description of Related Art
The use of free weights to build strength has been supplemented by various machines which permit exercise of isolated muscles or groups of muscles. Machines of this type restrict the movement of the part of the body being exercised to a defined path while the remainder of the body is relatively immobile. Such machines may involve the lifting of a weight through a system of levers and pulleys, and then lowering the weight. Machines of this type are sold under the trademarks "UNIVERSAL" and "NAUTILUS".
A major deficiency of these machines is that the velocity at which the weight is moved is controlled by the user. Many, if not most, users will move the weight at a velocity which is too fast for optimum muscle development.
Another problem is that the weight which is lowered is the same as the weight which is lifted, even though the muscles are capable of controlled lowering of a larger weight than they can lift. This controlled lowering of a weight, or negative resistance, is the most beneficial exercise for developing strength.
It is also desirable to perform a number of repetitions of each exercise, such as eight to twelve, so as to fatigue the muscle(s) being exercised. Because the capability of the muscles to perform the exercise decreases with each repetition, a weight which is less than the maximum which can be lifted is usually selected for the exercise. A preferred form is to have the weight for each repetition to be the maximum for that repetition; i.e. the weight should change with each repetition.
The weights used on these machines are in stacks with each weight being ten or twenty pounds. Unless one resorts to manually placing an additional smaller weight on the stack, a long period of time may pass until one can move up to the next highest weight. Although one is making progress during this time by being able to more readily complete the minimum repetitions or by adding repetitions, this extended time can be demoralizing. Even when one does reach the point of adding an additional weight, he is starting over with the minimum acceptable number of repetitions--eight. This may have a negative impact on the exerciser's motivation.
In spite of the foregoing deficiencies of these machines, they have been widely used and have improved the strength and conditioning of countless people.
A number of devices have been patented which provide additional capabilities to those of the machines referred to above. U.S. Pat. No. 4,235,437, Ruis et al, entitled "Robotic Exercise Machine and Method", discloses a hydraulic driven and controlled apparatus which can be programed to provide a number of different exercise paths for a user. These paths must be programmed for each new user by a trained technician. The device lacks the simplicity necessary for use in a health club or spa type environment. It also cannot be readily retrofitted on stacked weight type machines. Moreover, two separately controlled, hydraulically driven links are required for its operation.
U.S. Pat. No. 4,257,593, Keiser, entitled "Pneumatic Exercising Device", discloses a device which requires a compressed air supply. During the positive movement of the exercise handles the force required steadily increases, this maximum force must be resisted as the negative movement begins In addition, this apparatus fails to provide isokinetic control. The disclosed structure also does not provide for retrofitting on stacked weight type machines.
U.S. Pat. No. 4,544,154, Ariel, entitled "Passive Programmable Resistance Device", discloses a passive programmable resistance device which uses a closed loop feedback to control the resistance to be overcome. A computer is provided to store data pertaining to a user's performance for future analysis. Operation of the equipment is fairly complicated, militating against its use by the average person. Moreover, this apparatus does not provide isokinetic eccentric exercise, nor is it adapted to be readily applied to existing stacked weight machines.
U.S. Pat. No. 4,628,910, Krukowski, entitled "Muscle Exercise and Rehabilitation Apparatus", discloses apparatus for the application of constant resistive torque and/or constant velocity in both concentric and eccentric movement. A trained technician is necessary for the operation of this device. This apparatus is not adapted to be readily applied to existing stacked weight machines.
Devices have also been patented which couple an exercise cycle with a display and/or programmed varying resistance. U.S. Pat. No. 4,358,158, Sweeney, Jr., entitled "Programmed Exerciser Apparatus", provides for programming by the user for variation in the resistance exerted by the device.
U.S. Pat. No. 4,408,613, Relyea, entitled "Interactive Exercise Device", discloses apparatus which couples a varying resistance with a video monitor displaying an exercise program or race.
U.S. Pat. No. 4,542,897, Melton et al, entitled "Exercise Cycle with Interactive Amusement Device", provides a video game display.